Mars at perigee

Dominic Ford, Editor
From the Outer Planets feed


Objects: Mars

2257 apparition of Mars

21 Sep 2257 – Mars enters retrograde motion
18 Oct 2257 – Mars at perigee
26 Oct 2257 – Mars at opposition
27 Nov 2257 – Mars ends retrograde motion

Mars's orbit around the Sun will carry it to its closest point to the Earth – its perigee – passing within 0.43 AU of us.

The days around perigee represent the best time to observe Mars, since both its size and brightness in the night sky increase when it is close to us.

This effect is especially dramatic for Mars since it neighbours the Earth in the Solar System, orbiting a little further out from the Sun than us, at an average distance of 1.52 AU. As a result, it has the greatest variation of all the planets in its distance from the Earth, depending on whether the two planets are on opposite sides of the Sun, or passing next to one another in their respective orbits.

Mars reaches perigee at around the time when it passes the Earth in its orbit. At this time, the Sun, Earth and Mars lie in a straight line, with the Earth in the middle.

Consequently, Mars appears almost exactly opposite the Sun in the sky – a configuration called opposition, when Mars reaches its highest point in the sky at midnight and is visible for much of the night.

Every perigee of Mars is associated with a near-simultaneous opposition, but the two events typically occur a few days apart owing to the significant ellipticity of Mars's orbit.

On this occasion, Mars will attain a maximum angular diameter of 21.8 arcsec at closest approach, and a maximum brightness of magnitude -2.5 .

Observing Mars

Even at its closest approach to the Earth, it is never possible to distinguish Mars as more than a star-like point of light with the naked eye, though a simple pair of binoculars is sufficient to reveal it as a disk of light.

From South El Monte , it will be visible in the morning sky, becoming accessible around 19:20, when it reaches an altitude of 7° above your eastern horizon. It will then reach its highest point in the sky at 01:09, 66° above your southern horizon. It will be lost to dawn twilight around 06:26, 14° above your western horizon.

A chart of the path of Mars across the sky in 2257 can be found here, and a chart of its rising and setting times here.

The table below lists Mars' angular size and brightness at two-week intervals throughout its apparition:

Date Right ascension Declination Angular size Magnitude
17 Aug 225701h54m40s7°58'N14.7”-1.1
31 Aug 225702h13m10s9°34'N16.5”-1.4
14 Sep 225702h23m30s10°31'N18.5”-1.8
28 Sep 225702h23m10s10°47'N20.4”-2.1
12 Oct 225702h12m00s10°24'N21.7”-2.4
26 Oct 225701h54m00s9°39'N21.6”-2.5
09 Nov 225701h37m20s9°03'N20.0”-2.2
23 Nov 225701h28m40s9°05'N17.5”-1.7
07 Dec 225701h30m00s9°53'N15.0”-1.2
21 Dec 225701h40m10s11°21'N12.8”-0.8
04 Jan 225801h57m20s13°14'N11.0”-0.4

As Mars passes perigee, its position will be:

Object Right Ascension Declination Constellation Magnitude Angular Size
Mars 02h04m30s 10°06'N Pisces -2.5 21.8"

The coordinates above are given in J2000.0.

The sky on 22 Dec 2025

The sky on 22 December 2025
Sunrise
06:52
Sunset
16:46
Twilight ends
18:16
Twilight begins
05:22


Waxing Crescent

10%

3 days old

Planets
Rise Culm. Set
Mercury 05:39 10:39 15:38
Venus 06:39 11:33 16:28
Moon 09:11 14:09 19:11
Mars 07:16 12:09 17:01
Jupiter 18:17 01:23 08:29
Saturn 11:39 17:31 23:23
All times shown in PST.

Source

The circumstances of this event were computed using the DE430 planetary ephemeris published by the Jet Propulsion Laboratory (JPL).

This event was automatically generated by searching the ephemeris for planetary alignments which are of interest to amateur astronomers, and the text above was generated based on an estimate of your location.

Related news

18 Oct 2257  –  Mars at perigee
26 Oct 2257  –  Mars at opposition
27 Nov 2257  –  Mars ends retrograde motion
09 Nov 2259  –  Mars enters retrograde motion

Image credit

© NASA/Hubble Space Telescope

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